Blower

ABSTRACT

A blower ( 1 ) comprises a blast fan ( 20 ) provided within a casing ( 10 ), a driving unit ( 30 ) for rotationally driving the blast fan ( 20 ), a dust-proof cover ( 60 ) provided so as to cover an air intake ( 11 ) of the casing ( 10 ) and a drive stop mechanism ( 70 ) for stopping the driving unit ( 30 ). The drive stop mechanism ( 70 ) comprises a depressing lever ( 72 ) that depresses a pressure sensor ( 71 ) when it is pressed by a projection ( 65   b ) of the dust-proof cover ( 60 ) that is inserted into an attachment hole ( 12 ) of the casing ( 10 ) and a control section ( 73 ) for stopping the driving unit ( 30 ) when the pressure acting on the pressure sensor ( 71 ) from the depressing lever ( 72 ) decreases. This structure allows safety of the blower to be improved when the dust-proof cover ( 60 ) is removed from the air intake ( 11 ) and the air intake ( 11 ) is exposed to the outside because the rotation of the blast fan ( 20 ) automatically stops.

BACKGROUND OF THE INVENTION

1. Technical Field of Invention

The present invention relates to a blower for sweeping objects such as dead leaves and sprigs deposited on the ground by blowing them away and also for cleaning dusts by vacuuming them up.

2. Description of the Related Art

As a blower for sweeping objects such as dead leaves and sprigs deposited on the ground by blowing them away, there is one having a blast fan provided within a casing, an engine for rotationally driving the blast fan and a blast duct for discharging an air flow generated by the rotating blast fan to the outside.

Such a blower is provided with a grip attached to the casing and an operator can carry around the blower by holding the grip. Then, the operator can blow and sweep the objects such as dead leaves and sprigs by discharging the high-speed air flow to the ground out of an air outlet of a blower pipe coupled with the blast duct.

The casing of the blower is provided also with an air intake for taking fresh air into the casing and the fresh air suctioned into the casing from the air intake becomes the high-speed air flow by the rotating blast fan as the fan is rotated.

The blower constructed as described above may be also provided with a cylindrical vacuum pipe at the air intake and with a net-like dust collecting bag at the blast duct to vacuum up and collect the dusts from a suction mouth of the vacuum pipe as disclosed in Japanese Patent Application Laid-open No. 2005-163765 for example. Thus, the blower may be utilized also as a vacuum cleaner.

It is noted that because the air intake of the blower is provided with a dust-proof cover to prevent from sucking extraneous materials, it is necessary to remove the dust-proof cover and to expose the air intake to the outside in order to attach the vacuum pipe to the air intake. At this time, there is a problem that the blower must be handled carefully when the blast fan is rotating within the casing.

SUMMARY OF THE INVENTION

In order to deal with the problem of the prior art described above, the inventor has promoted research and development and has invented the present invention. That is, one aspect of the invention is to provide a blower whose safety is improved by automatically stop rotation of a blast fan when a dust-proof cover is removed from an air intake and the air intake is exposed to the outside.

More specifically, the blower of one aspect of the invention has the blast fan provided within a casing, a driving unit for rotationally driving the blast fan, a blast duct for discharging an air flow generated by the rotating blast fan to the outside, a dust-proof cover provided so as to cover an air intake formed in the casing and a drive stop mechanism for stopping the driving unit. The blower is characterized in that the dust-proof cover is attached to the casing by inserting a projection provided in the dust-proof cover into an attachment hole formed in the casing and that the drive stop mechanism has a pressure sensor provided in the casing, a depressing lever whose one end contacts with a detecting part of the pressure sensor and whose other end is disposed in the attachment hole and one end depresses the detecting part of the pressure sensor when the other end is pressed by the projection that is inserted into the attachment hole and a control section for setting up the driving unit into a drivable state when a pressure acts on the detecting part of the pressure sensor and for setting up the driving unit into a stop state when the pressure acting on the detecting part of the pressure sensor decreases.

When the dust-proof cover is removed out of the air intake and when the projection of the dust-proof cover moves in a direction of being pulled out of the attachment hole of the casing, the pressure acting on the other end of the depressing lever from the projection decreases in this arrangement. Due to that, the pressure acting on the detecting part of the pressure sensor from one end of the depressing lever also decreases, so that the control section sets up the driving unit into the stop state.

Still more, because the control section is arranged so that it sets up the engine of the driving unit into the haling state when the pressure acting on the pressure sensor by the depressing lever decreases, the engine halts when the projection of the attachment screw of the dust-proof cover is not completely pulled out, i.e., when the attachment screw of the dust-proof cover is loosened.

Thus, the engine is put into the stop state and the blast fan stops from rotating before the air intake of the casing is exposed to the outside, so that it is possible to improve the safety of the blower in opening the dust-proof cover from the air intake.

Still more, because the control section changes the driving states of the engine of the driving unit based on the variation of the pressure applied to the pressure sensor that varies depending on whether or not the dust-proof cover is attached, it is readily possible to change over the driving states of the driving unit.

Still more, the intermediate portion of the depressing lever is exposed to the inner peripheral face of the air intake in the blower described above, so that it is possible to arrange so that one end of the depressing lever depresses the detecting part of the pressure sensor when the suction pipe inserted into the air intake depresses the intermediate portion of the depressing lever.

Further, because the control section changes the states of the driving unit from the stop state to the drivable state when the vacuum pipe is attached to the air intake and the depressing lever depresses the detecting part of the pressure sensor, it is thus possible to change over the driving states of the driving unit with this arrangement.

The various aspects and effects of the invention described above as well as other effects and features thereof will be more clearly understood by the following detailed explanation of illustrative and nonrestrictive embodiments of the invention made with reference to the appended drawings.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 shows a blower of a present embodiment and is a perspective view seen from a front side thereof in a state in which a dust-proof cover is closed.

FIG. 2 shows the blower of the present embodiment and is a perspective view seen from the front side thereof in a state in which the dust-proof cover is opened.

FIG. 3A and FIG. 3B show a drive stop mechanism of the blower of the embodiment, wherein FIG. 3A is a transverse section view showing a state in which the dust-proof cover is closed and FIG. 3B shows a transverse section view showing a state in which the dust-proof cover is opened.

FIG. 4 is a diagrammatic structural view showing the drive stop mechanism of the blower of the embodiment.

FIG. 5 is a perspective view showing the blower of the embodiment seen from the front side thereof in a state in which a vacuum pipe is attached.

FIG. 6 is a transverse section view showing the drive stop mechanism of the blower of the embodiment in a state in which the vacuum pipe is attached.

DETAILED DESCRIPTION OF THE INVENTION

Embodiments for carrying out the invention will be explained in detail below with reference to the drawings. It is noted that front and back and right and left directions in the following explanation are directions seen from an operator in using a blower and correspond to front and back and right and left directions shown in each drawing.

[Whole Structure of Blower]

The blower 1 of the present embodiment shown in FIG. 1 is a power blower for sweeping objects such as dead leaves and sprigs deposited on the ground by blowing them away and for cleaning by vacuuming dusts up and includes a blast fan (not shown) provided within a casing 10, a driving unit 30 for rotationally driving the blast fan, a blast duct 40 for discharging an air flow generated by the rotating blast fan to the outside and a drive stop mechanism (not shown) for setting driving states of the driving unit 30.

This blower 1 is provided with a grip 50 on the casing 10 and the driving unit 30 and the operator can carry around the blower 1 by holding the grip 50. Then, the operator can sweep dusts such as dead leaves and springs by blowing them away by discharging the high-speed air flow from an air outlet of a blower pipe P1 coupled with the blast duct 40.

Still more, as shown in FIG. 5, the blower 1 of the embodiment may be also provided with a cylindrical vacuum pipe P2 (suction pipe) at an air intake 11 formed in the casing 10 and with a net-like dust collecting bag B at the blast duct 40 to vacuum up and collect the dusts from a suction mouth of the vacuum pipe P2. Thus, the blower 1 may be utilized also as a vacuum cleaner.

(Structure of Casing, Blast Fan and Blast Duct)

The casing 10 is a substantially circular box when seen from the side as shown in FIG. 1 and is provided with a blast fan (not shown) at the center part thereof.

The blast fan 20 shown in FIG. 3A and FIG. 3B has a plurality of vanes 21 formed around a rotary shaft (not shown) extending in the front-back direction in the center part of the casing 10. The blower 1 is constructed so that the blast fan 20 generates the high-speed air flow in a direction from the outside to the inside of the casing 10 when the blast fan 20 is rotating around the rotary shaft.

Still more, as shown in FIG. 2, the blower 1 is provided with the air intake 11 for taking ambient air into the casing 10 at the left side face of the casing 10. The air intake 11 is circular when seen from the front side and is formed at position approaching the blast fan (not shown) (see FIG. 3A and FIG. 3B).

The blower 1 is also provided with a cylindrical blast duct 40 attached at the front part of the casing 10 to discharge the air flow generated by the rotating blast fan to the outside of the casing 10.

Then, the ambient air taken into the casing 10 through the air intake 11 becomes the high-speed air flow by the rotating blast fan as the blast fan is rotating. This air flow is discharged to the outside through the blast duct 40.

(Structure of Driving Unit)

As shown in FIG. 1, the driving unit 30 is provided on the right side portion of the casing 10 and has an engine (not shown) stored within a box-like engine cover 31 attached on the right side portion of the casing 10. An output shaft of the engine is linked with the rotary shaft of the blast fan (not shown) so that the engine of the driving unit 30 rotates the blast fan by its driving force.

(Structure of Dust-proof Cover)

As shown in FIG. 1, the air intake 11 (see FIG. 2) of the casing 10 is covered by a dust-proof cover 60 for preventing extraneous materials from being sucked into the casing 10.

The dust-proof cover 60 has an outer peripheral plate 62 rising to the casing 10 side at an outer periphery of a side plate 61 that is seen circular from the side. A lattice-like opening 63 is formed through the side plate 61 and the peripheral plate 62.

A rear end portion of the peripheral plate 62 of the dust-proof cover 60 is attached to a rear side portion of the air intake 11 on the left side of the casing 10 by means of a hinge 64 as shown in FIG. 2. Thereby, the dust-proof cover 60 is capable of turning about hinge 64 in the front-back direction and opening the air intake 11.

The dust-proof cover 60 is also provided with an attachment screw 65 at a front end part of the peripheral plate 62. As shown in FIG. 3A, the attachment screw 65 is composed of a knob 65 a provided on an outer surface side of the dust-proof cover 60 and a projection 65 b inserted into a through hole 66 perforated through the dust-proof cover 60. The projection 65 b has a male thread formed thereon. The projection 65 b is also provided with a rubber ring 65 c fitted to retain it in the through hole 66.

When the dust-proof cover 60 is closed (see FIG. 1), the projection 65 b of the attachment screw 65 is inserted into an attachment hole 12 (see FIG. 2) formed on the front side of the air intake 11 of the casing 10. It is noted that a female thread is formed on an inner peripheral surface of the attachment hole 12.

The projection 65 b is screwed into the attachment hole 12 when the operator turns the whole attachment screw 65 around its axis by holding a knob 65 a of the attachment screw 65 in the state in which the projection 65 b of the attachment screw 65 is inserted into the attachment hole 12. Thus, the front end part of the dust-proof cover 60 may be fixed to the casing 10.

Then, when the blast fan (not shown) rotates in the state in which the dust-proof cover 60 is closed as shown in FIG. 1, the ambient air is taken into the dust-proof cover 60 through the opening 63 and is suctioned into the casing 10 through the air intake 11 (see FIG. 2). Thus, the rotating blast fan generates the high-speed air flow.

[Structure of Drive Stop Mechanism]

The drive stop mechanism 70 shown in FIG. 3A and FIG. 3B is a control mechanism that sets the engine 32 (see FIG. 4) of the driving unit 30 in a drivable state when the dust-proof cover 60 is closed over the air intake 11 and sets the engine 32 in a stop state when the dust-proof cover 60 is opened from the air intake 11.

The drive stop mechanism 70 has a pressure sensor 71 provided within the casing 10, a depressing lever 72 that contacts with a detecting part 71 a of the pressure sensor 71 as shown in FIG. 3A and a control section 73 (see FIG. 4) that sets the driving state of the engine 32 of the driving unit 30 based on a detected signal transmitted from the pressure sensor 71.

(Structure of Pressure Sensor)

The pressure sensor 71 shown in FIG. 3B may be any type of conventionally known pressure sensors that detect pressure applied to the detecting part 71 a and outputs the detected signal indicating variation of the pressure to the control section 73 (see FIG. 4). However, its structure is not limited to that.

The pressure sensor 71 is installed within a hollow space 13 created on the front side of the air intake 11 in the casing 10. The hollow space 13 has an opening and communicates with the air intake 11, and also communicates with an opening on the inner side of the attachment hole 12. The pressure sensor 71 is disposed near an opening 13 a on the side of the air intake 11 within the hollow space 13.

(Structure of Depressing Lever)

The depressing lever 72 has a member substantially having a shape of Z when seen planarly as shown in FIG. 3B and is disposed within the hollow space 13 created in the casing 10. A cardinal end portion 72 a (one end) of the depressing lever 72 contacts with the detecting part 71 a of the pressure sensor 71 and a front end portion 72 b (other end) is inserted into the attachment hole 12 of the casing 10.

Specifically, the cardinal end portion 72 a of the depressing lever 72 is disposed on the side of the air intake 11 within the hollow space 13 and a front face of the cardinal end portion 72 a contacts with the detecting part 71 a of the pressure sensor 71.

Still more, the cardinal end portion 72 a has a through hole 72 e formed further inward from the point at which the cardinal end portion 72 a is in contact with the pressure sensor 71. The depressing lever 72 is attached to the casing 10 through an anchoring shaft 72 d inserted through the through hole 72 e and pivots about the anchoring shaft 72 d.

Further, an intermediary portion 72 c of the depressing lever 72 located outward from the cardinal end portion 72 a is formed so as to be inserted into the opening 13 a on the air intake 11 side. Accordingly, the intermediate portion 72 c of the depressing lever 72 is exposed to the air intake 11 through the opening 13 a.

The intermediate portion 72 c of the depressing lever 72 extends from the cardinal end portion 72 a toward the outside and also extends forward from an outer end portion of the depressing lever 72 to a position facing the inner-side opening of the attachment hole 12.

The front end portion 72 b of the depressing lever 72 formed at the position facing the inner-side opening of the attachment hole 12 extends toward the outside and is inserted into the attachment hole 12.

The drive stop mechanism 70 is arranged to have the projection 65 b of the attachment screw 65 press the front end portion 72 b of the depressing lever 72 as shown in FIG. 3A.when the projection 65 b of the attachment screw 65 of the dust-proof cover 60 is inserted into the attachment hole 12 of the casing 10, i.e., when the dust-proof cover 60 is closed (see FIG. 1).

When the projection 65 b of the attachment screw 65 thus presses the front end portion 72 b of the depressing lever 72, the front end portion 72 b of the depressing lever 72 is pushed inward. Thereby, the whole depressing lever 72 turns inclined about the anchoring shaft 72 d in a direction of an arrow A in FIG. 3A.

When the whole depressing lever 72 turns inclined in the direction of the arrow A, the cardinal end portion 72 a of the depressing lever 72 depresses the detecting part 71 a of the pressure sensor 71 and the pressure sensor 71 outputs the detected signal to the control section 73 (see FIG. 4).

On the other hand, when the projection 65 b of the attachment screw 65 of the dust-proof cover 60 is not inserted into the attachment hole 12, i.e., when the dust-proof cover 60 is opened (see FIG. 2), no pressure is applied to the front end portion 72 b of the depressing lever 72 as shown in FIG. 3B. Accordingly the depressing lever 72 does not turn inclined in this case and no pressure is applied to the detecting part 71 a of the pressure sensor 71. As a result, the pressure sensor 71 outputs no detected signal to the control section 73 (see FIG. 4).

Still more, when the vacuum pipe P2 is inserted into the air intake 11 (see FIG. 5) with the dust-proof cover 60 opened as shown in FIG. 6, an engaging projection P21 formed on the peripheral surface of the vacuum pipe P2 is inserted into the opening 13 a of the hollow space 13 formed on the side of the air intake 11.

Thus the engaging projection P21 inserted into the opening 13 a depresses the intermediate portion 72 c of the depressing lever 72 and the intermediate portion 72 c is pushed toward the front side. Thereby, the whole depressing lever 72 turns inclined about the anchoring shaft 72 d in the direction of the arrow A.

Then, when the whole depressing lever 72 turns inclined in the direction of the arrow A, the cardinal end portion 72 a of the depressing lever 72 depresses the detecting part 71 a of the pressure sensor 71 and the pressure sensor 71 outputs the detected signal to the control section 73 (see FIG. 4).

(Structure of Control Section)

The control section 73 shown in FIG. 4 performs the drive control of the engine 32 in response to the variation of the pressure applied to the detecting part 71 a of the pressure sensor 71. It is noted that the control section 73 is constructed by using various known control circuits and its structure is nonrestrictive.

The control section 73 sets up the engine 32 of the driving unit 30 into the drivable state when the depressing lever 72 applies the pressure to the detecting part 71 a of the pressure sensor 71 and the pressure sensor 71 outputs the detected signal in such cases when the dust-proof cover 60 is closed (see FIG. 3A) and when the vacuum pipe P2 is inserted into the air intake 11. The engine 32 may be driven to rotate the blast fan 20 in this state.

The control section 73 also sets up the engine 32 in the driving unit 30 into the stop state when the depressing lever 72 applies no pressure to the detecting part 71 a of the pressure sensor 71 and the pressure sensor 71 outputs no detected signal in such a case when the dust-proof cover 60 is opened (see FIG. 3B). The engine 32 is stopped and the blast fan 20 is stopped from rotating in this state. Still more, because the engine 32 is kept stopped, the blast fan 20 cannot rotate by any erroneous operation.

The control section 73 is also arranged to set up the engine 32 of the driving unit 30 into the stop state when the pressure being applied to the detecting part 71 a of the pressure sensor 71 decreases.

Accordingly, the engine 32 is put into the stop state when the attachment screw 65 shown in FIG. 3A is loosened and when the pressure of the depressing lever 72 applied to the detecting part 71 a of the pressure sensor 71 decreases. The engine 32 stops in this state and the rotation of the blast fan 20 stops as well. Still more, because the engine 32 is kept stopped, the blast fan 20 cannot rotate by any erroneous operation.

[Actions and Effects of Blower]

When the dust-proof cover 60 is opened and when the projection 65 b of the attachment screw 65 of the dust-proof cover 60 moves in a direction of being pulled out of the attachment hole 12 of the casing 10 as shown in FIG. 3A and FIG. 3B, the pressure applied to the front end portion 72 b of the depressing lever 72 from the projection 65 b decreases in the blower 1 of the present embodiment.

With the pressure applied to the front end portion 72 b decreasing, the pressure applied to the detecting part 71 a of the pressure sensor 71 from the cardinal end portion 72 a of the depressing lever 72 also decreases and the control section 73 sets up the engine 32 (see FIG. 4) of the driving unit 30 into the stop state.

Thus, the engine 32 is put into the stop state and the blast fan 20 automatically stops from rotating when the dust-proof cover 60 is opened, so that it becomes possible to improve the safety of the blower 1 when the air intake 11 is exposed to the outside in attaching/detaching the vacuum pipe P2 to/from the air intake 11 (see FIG. 5) or when the dust-proof cover 60 is removed during operation.

Still more, because the control section 73 (see FIG. 4) is arranged to set up the engine 32 (see FIG. 4) of the driving unit 30 into the stop state when the pressure applied to the pressure sensor 71 from the depressing lever 72 decreases, the engine 32 halts also when the projection 65 b of the attachment screw 65 of the dust-proof cover 60 is not completely pulled out, i.e., when the attachment screw 65 of the dust-proof cover 60 is loosened.

Thus, the engine 32 is put into the stop state and the blast fan 20 stops from rotating before the air intake 11 of the casing 10 is exposed to the outside, so that it is possible to improve the safety of the blower 1 in opening the dust-proof cover 60 from the air intake 11.

Still more, because the control section 73 (see FIG. 4) changes the driving states of the engine 32 of the driving unit 30 in response to the variation of the pressure applied to the pressure sensor 71 that varies depending on whether or not the dust-proof cover 60 is attached, it is readily possible to change over the driving states of the engine 32.

Furthermore, because the control section 73 (see FIG. 4) changes the states of the engine 32 from the stop state to the drivable state when the vacuum pipe P2 is attached to the air intake 11 and the depressing lever 72 depresses the detecting part 71 a of the pressure sensor 71, it is thus possible to change over the driving states of the engine 32.

[Other Embodiment]

While the embodiment has been explained as an exemplary case of the invention, the embodiment may be modified or changed variously within a spirit and scope of the invention defined by the appended claims.

For example, although the attachment screw 65 of the dust-proof cover 60 is screwed into the attachment hole 12 of the casing 10 as shown in FIG. 3B in the present embodiment, a projection such as a pin and a hook formed on the dust-proof cover 60 may be fitted into an attachment hole formed in the casing 10 to secure the dust-proof cover 60 to the casing 10 and to press the depressing lever 72 by the projection.

Still more, although the present embodiment is arranged such that the dust-proof cover 60 is attached to the casing 10 by the hinge 64 so that the dust-proof cover 60 opens/closes as shown in FIG. 2, it is also possible to arrange such that the whole dust-proof cover may be removed out of the side of the casing 10. 

1. A blower, comprising a blast fan provided within a casing, a driving unit for rotationally driving the blast fan, a blast duct for discharging an air flow generated by the rotating blast fan to an outside, a dust-proof cover provided to cover an air intake formed in the casing and a drive stop mechanism for stopping the driving unit, wherein the dust-proof cover is attached to the casing by inserting a projection provided in the dust-proof cover into an attachment hole formed in the casing, and wherein the drive stop mechanism comprises: a pressure sensor provided in the casing; a depressing lever having a first end in contact with a detecting part of the pressure sensor and a second end which is disposed in the attachment hole and is pressed by the projection that is inserted into the attachment hole so as to have the first end depresses the detecting part of the pressure sensor; and a control section for setting up the driving unit into a drivable state if a pressure applied to the detecting part of the pressure sensor and for setting up the driving unit into a stop state if the pressure applied to the detecting part of the pressure sensor decreases.
 2. The blower according to claim 1, wherein the depressing lever has an intermediary portion of the depressing lever exposed to an the air intake and is formed to have the first end of the depressing lever presses the detecting part of the pressure sensor if the intermediate portion of the depressing lever is pressed by a suction pipe inserted into the air intake. 